abstract |
This invention provides compounds of the following formula WHEREIN R1 is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a hydroxyalkyl group having 2 to 4 carbon atoms, a benzyl group, a benzyl group substituted by methoxy, a phenyl group, a propargyl group or an acyl group; R2 is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkyl group having 2 to 4 carbon atoms substituted by hydroxy or halogen, a vinyl group, an allyl group, or a benzyl group R3 is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms; AND SALTS THEREOF, AND PROCESSES FOR PREPARING THEM. Some of the compounds have antibacterial activities. |